Identify which of the following is/are the correct reason/s why rem is the preferred unit when measuring the health impacts of radiation.
I. The rem (roentgen equivalent for man) takes into account both biological effect and ionizing intensity through the equation: Rems = RBE × rads.
II. The value of rems gives the amount of tissue damage due to radiation. 
III. Rem indicates the capacity of radiation to affect matter.
IV. Rem measures equivalent doses of different types of radiation in the medical field.
V. Rem incorporates the relative biological effectiveness factor, which takes into account the different radiation types and energy differences.